The engine immobiliser system is designed to prevent the vehicle from being stolen. This system uses a transponder key ecu that stores the key codes of authorized ignition keys. If an attempt is made to start the engine using an unauthorized key, the ecu sends a signal to the ecm to prohibit fuel delivery and ignition, effectively disabling the engine.

The transponder key coil receives this signal, the transponder key amplifier amplifies it, and then the signal is transmitted to the ecu. The ecu matches the key's id code with the vehicle's id code, which was previously registered in the ecu and then communicates the results to the ecm using sfi communication.
Engine immobiliser system
How to proceed with troubleshootingElectronic control
Removal and installation of battery
terminal
Notice:
Certain systems need to be initialized after
disconnecting and reconnecting the cable from
the negative (-) battery terminal.
Before performing electronic work, disconnect
the cable from the negative (-) battery terminal to
...
Terminals of ecu
Skid control ecu
Hint:
*1: W/ 16-inch disc
*2: W/ downhill assist control
*3: For 2wd (w/ auto lsd)
Check skid control ecu
Disconnect the a19 ecu connector.
Measure the voltage and resistance of the wire
harness side connector.
Hint:
The voltage cannot be measured ...
Inspection
Inspect camshaft timing oil control valve
assembly
Measure the resistance of the oil control valve.
Standard resistance
If the result is not as specified, replace the oil control
valve assembly.
Check the operation.
Apply battery voltage across the terminals and
chec ...